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And if you care about performance, you > won't be using an old compiler. The minimal GCC version is 8.1, and asm goto with outputs is supported since GCC-11. That would brake the build, if we just switch to using it without "CC_IS_GCC && (GCC_VERSION >= 110100)" guard. Is it worth to maintain 2 version of the function? I don't know... Thanks, Yury